Patent · US Expired

Electronic timepiece with electrochromic display

US4443115A · kind A · utility

3Cited by
6References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 2, 1981
Grant dateApr 17, 1984
Priority date
Expiry dateJan 2, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG04G9/0029
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An electronic timepiece provided with an electrochromic display device as a time related information display. The ECD is driven by an electric charge transfer method. The electric charges which cause coloration of segments directly transfer from non-selected segments to selected segments. In the ECD additional concealed dummy segments temporally store the excess electric charges when the total area of the selected segments decreases, and release the stored electric charges when the total area of the selected segments increases, so that the electric charge density of colorized segment is always kept constant. Moreover electric charges are periodically supplied to the display device so as to compensate the lost amount which was dissipated during transfer cycle.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.